This study extends the research on asynchronous online discussion (AOD) by providing a perspective on: (1) the growth patterns of discussion threads and (2) the influence of peer- or student-facilitation techniques on thread development. Using the Pointing, Questioning, Resolving and Summarizing (PQRS) facilitation techniques framework, the threaded discussions of seven AOD forums were carefully mapped out and each message in the postings was examined to determine the type of facilitation techniques applied. Results suggest that an online discussion thread grows either one of three patterns: a "short thread pattern", an "extended thread pattern" with an elongated structure or a "split thread pattern" with a broad structure. Results also suggest that the use of Resolving and Summarizing facilitation techniques tends to foster early thread termination. Understanding how each PQRS student-facilitation technique impacts thread development reinforces the need to combine the use of "questioning" techniques with other facilitation techniques to enhance thread continuity. We end by discussing some possible implications and issues for future research.